1. Field of the Invention
The present invention relates to a linear motor.
2. Description of the Related Art
As a linear motor used for table feed, there has been suggested a structure disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2010-63201 published Mar. 18, 2010. The structure includes a field arranged to face an armature with a gap (magnetic gap) interposed therebetween. The field includes main-magnetic-pole permanent magnets magnetized in a direction of a generation magnetic field, and sub-magnetic-pole permanent magnets magnetized in a direction different from the direction of magnetic poles of the main-magnetic-pole permanent magnets. Portions of the main-magnetic-pole permanent magnets located at a magnetic-field generation side are replaced with soft magnetic materials. Hence, the structure has so-called Halbach array.